A multi-stage thermal management system includes a fluid loop configured to supply a chilled heat transfer fluid to a plurality of thermal loads having different cooling demands. The system includes a plurality of heat rejection components arranged in stages and fluidly coupled to the fluid loop. The plurality of heat rejection components is configured to receive a return heat transfer fluid from the plurality of thermal loads and extract heat from the return heat transfer fluid to generate the chilled heat transfer fluid. A control system is configured to selectively draw the chilled heat transfer fluid from each heat rejection component individually and to direct the chilled heat transfer fluid to the plurality of thermal loads based on the different cooling demands of the plurality of thermal loads to meet each of the different cooling demands via supply of the chilled heat transfer fluid.

An air conditioning system comprises one or more air conditioners through which refrigerant circulates, and a first controller. For each of one or more indoor units, a score corresponding to a cost of using the indoor unit is preset. The first controller calculates, for each of the one or more air conditioners, a first total value of a score of each of the one or more indoor units included in the air conditioner. The first controller calculates a second total value of the first total value of each of the one or more air conditioners. When an electrical energy limit condition is satisfied, the first controller sets for each of the one or more air conditioners a drive frequency for a compressor included in the air conditioner according to a ratio of the first total value of the air conditioner to the second total value.

An air conditioner may include: an outdoor unit including a compressor and an outdoor heat exchanger; a first indoor unit including a first indoor heat exchanger; and a second indoor unit including a second indoor heat exchanger and an indoor expansion valve, wherein the outdoor unit includes: a first outdoor pipe, an outdoor expansion valve provided in the first outdoor pipe, the first outdoor pipe allowing a refrigerant discharged from the outdoor heat exchanger to pass through the outdoor expansion valve and flow to the first indoor unit; and a second outdoor pipe allowing a refrigerant discharged from the outdoor heat exchanger to bypass the outdoor expansion valve and flow to the second indoor unit.

An indicator outputs information relating to a heat-pump system including a plurality of usage-side units which form a communication network. The indicator includes a mode management section configured to accept selection from a plurality of operation modes of the indicator including a first mode, a unit-side communication section configured to receive or acquire first and second unit signals from a predetermined usage-side unit of the usage-side units, and an indicator output section. The first unit signal is used for information originated by the predetermined usage-side unit. The second unit signal is used for information not originated by the predetermined usage-side unit. The indicator output section is configured to, when alarm information has been received or acquired via a second unit signal while the indicator is operating in a first mode, output the alarm information.

A control device controls a heating capacity during a heating operation and a defrosting capacity during a defrosting operation. The defrosting capacity of the first refrigeration cycle unit is determined to fall within a range satisfying a first determination condition and within a range satisfying a second determination condition. The first determination condition is a condition that a sum of a load capacity of a load device when the first defrosting start condition is satisfied, and the defrosting capacity of the first refrigeration cycle unit does not exceed the heating capacity of a second refrigeration cycle unit. The second determination condition is a condition that a sum of an inter-unit defrosting interval and a defrosting period of the first refrigeration cycle unit does not exceed a shortest defrosting interval of the second refrigeration cycle unit.

Chiller control systems and methods for chiller control use iterative modeling of cooling towers, heat exchangers, and pumps to determine the feasibility of integrated free cooling and the ability to take advantage of free cooling. The control systems and control methods can further include selecting the parameters for operating in the free cooling or integrated free cooling mode to improve efficiency and/or reduce energy consumption when operating in these modes. The models can have inputs and outputs that feed into one another, and converge at a solution over multiple iterations. The feasibility of integrated free cooling can be based on providing cooling to a cooling load process fluid at a heat exchanger. The availability of free cooling can be based on the cooling provided at the heat exchanger achieving a target temperature for the cooling load process fluid.

A control method includes, after a multi-split air conditioner starts to operate in a heating mode, determining a target room from a plurality of rooms for which the multi-split air conditioner provides air conditioning, obtaining an indoor temperature of the target room, determining whether the indoor temperature of the target room is greater than a target temperature corresponding to the target room, and, in response to a determination that the indoor temperature of the target room is greater than the target temperature, controlling the multi-split air conditioner to switch an operation mode of a target indoor unit corresponding to the target room from the heating mode to a cooling mode.

A refrigerating and air-conditioning apparatus performs, even during a heating operation under air conditions leading to formation of frost, a defrosting operation while simultaneously continuing the heating operation and improves comfort through heating by securing an appropriate amount of ventilation. A plurality of refrigeration cycles independently performs a heating operation and a defrosting operation. By controlling a ventilation damper of an indoor unit that is to perform a defrosting operation to increase the amount of ventilation, a prior ventilation operation for securing the time-averaged required amount of ventilation including the period in which the defrosting operation is being performed is performed before the defrosting operation, and after the prior ventilation is terminated, the defrosting operation is started.

A chilled beam includes a body having a first side and a second side opposite to the first side. The chilled beam also includes a first mounting bracket coupled to the first side and configured to rotate against a first bias of the first mounting bracket in response to a first force against the first mounting bracket. The chilled beam also includes a second mounting bracket coupled to the second side and configured to rotate against a second bias of the second mounting bracket in response to a second force against the second mounting bracket.

A water regulator includes a water regulation valve, a first temperature sensor, a second temperature sensor, and a controller. The water regulation valve regulates a quantity of water flowing through water pipes. The first temperature sensor measures a temperature of one of the water pipes which is connected to an inlet of a heat exchanger. The second temperature sensor measures a temperature of one of the water pipes which is connected to an outlet of the heat exchanger. The controller controls an opening degree of the water regulation valve, based on a difference between the temperature measured by the first temperature sensor and the temperature measured by the second temperature sensor.